What are performance implications of increasing RAM clock speed while increasing latency?

Nickolai · Aug 13, 2017

As clock speeds of computer RAM modules get higher (resulting in higher performance), its latency measured in clocks tends to get higher (resulting in lower performance). How does one determine when the trade-off is worth it and how much is it worth? If there are both benefits and drawbacks to it, what are they?

Take, for example, two DDR4 memory modules from Kingston: HyperX Savage HX424C12SB2/4 and HX426C13SB2/4. Their stated specifications are as follows:

HX424C12SB2/4:

JEDEC: DDR4-2133 CL15-15-15 @1.2V
XMP Profile #1: DDR4-2400 CL12-14-14 @1.35V
XMP Profile #2: DDR4-2133 CL13-13-13 @1.2V

HX426C13SB2/4:

JEDEC: DDR4-2133 CL15-15-15 @1.2V
XMP Profile #1: DDR4-2666 CL13-15-15 @1.35V
XMP Profile #2: DDR4-2400 CL13-14-14 @1.35V

Clearly, these modules are the same performance-wise at JEDEC timings at 2133 MHz (both CL15-15-15). Apparently, HX424C12SB2/4 is faster as 2400 MHz (CL12-14-14 vs. CL13-14-14). At their top speed, however, it is DDR4-2400 CL12-14-14 vs. DDR4-2666 CL13-15-15. What are performance implications of this and if there are both benefits and drawbacks to both modes, what are they?

daswilhelm · Aug 13, 2017

Depends on the platform you are using. Intel systems (recent ones) seem to prefer tighter timings, while Ryzen benchmarks seem to favor higher speed ram kits (to a point). So it depends on your machine, and what you are using it for.

Search

What are performance implications of increasing RAM clock speed while increasing latency?

Nickolai

Distinguished

daswilhelm

daswilhelm

Splendid

TRENDING THREADS

Latest posts

Moderators online

Share this page